By GREG JOHNS, P-I REPORTER

Updated 10:00 pm, Wednesday, April 4, 2007

The Mariners got off to a nice hot start this season by taking their opening series against the Oakland A's, but things are about to cool off considerably.

After playing in moderately temperate early April weather in Safeco Field, the Mariners embark on a seven-day road swing that begins Friday in chilly Cleveland. Forecasts in Ohio call for snow showers and temperatures in the upper 20s through the weekend.

New Mariners starter Horacio Ramirez is a California native who spent his first four years in the big leagues in Atlanta. He'll be on the mound Friday afternoon for the Indians' home opener at Jacobs Field (1:05 p.m., no TV).

"I don't think I've ever pitched in the snow," Ramirez said. "But in Atlanta we always played Philadelphia early every year and it was about the same temperatures (as Cleveland). You're just cold when you're out there getting loose, but once the game starts, it's time to forget about it."

Jeff Weaver, who'll make his Mariners' debut Saturday against Cleveland's C.C. Sabathia, is a little more familiar with cold-weather outings. Weaver also grew up in California, but pitched in Detroit from 1999-2002.

He recalls Opening Day in Detroit in 2000 when the Tigers played in a driving sleet, as well as some miserably cold and windy days in Chicago.

"I never get used to it," Weaver said. "It's bone-chilling. During the World Series and playoffs in Detroit and St. Louis, it was 28-30 degrees. You just hope the adrenaline is pumping."

Weaver said he tries to stay warm and work up a sweat in the clubhouse before going to the mound each inning. He figures he has one edge in those situations.

"If you get loose before you head out there, I think the pitcher definitely has an advantage because the position players are just standing or sitting around," he said. "And when it's cold, that bat and ball get a little heavier."

Felix Hernandez, 20, the Mariners' youngest player, doesn't have much experience with blustery weather. The Venezuelan said the coldest conditions he's ever faced were when it was 45 degrees at Safeco Field.

Hernandez is scheduled to start Sunday in the third game of the four-game series. The Mariners conclude their trip with three games in Boston, where temperatures in the mid-40s are expected.

BETANCOURT TO COURT: Mariners shortstop Yuniesky Betancourt expects to miss Friday's game in Cleveland. He's been called to testify in court in Key West, Fla., in the smuggling trial of his former agent, Gustavo Dominguez.

Dominguez faces charges on 53 counts of trying to smuggle Cuban players into the United States.

Betancourt flew to Florida after Wednesday's game and is scheduled to be called some time Friday. He figures he won't get done in time to get to Cleveland for the Mariners game, scheduled for 1:05 p.m.

"I don't know how long the court is," Betancourt said. "Hopefully I'll get back Saturday, but I don't think so on Friday."

Mariners general manager Bill Bavasi said the expectation is that Betancourt's role in the trial will be finished Friday and he won't be called back for any further appearances.

SEXSON SLUGGING: First baseman Richie Sexson's two home runs in his first two games equaled his long-ball production his first month of the 2006 season.

Sexson hit two home runs in the first nine games last season, but finished April with just those two in 94 at-bats. He hit his third homer on May 1.

Sexson isn't always a slow starter, however. He hit two home runs on Opening Day of his initial season in Seattle in 2005 and finished April with six that year.

Only 18 players have homered in the season's first three games, and the major league record of four consecutive games to start the season is shared by Willie Mays (Giants, 1971) and Mark McGwire (Cards, 1998).

BIRTHDAY BOY: Hernandez has pitched his last game as a 20-year-old. The young ace makes his next start Sunday on his 21st birthday, but says he'll take no special significance in that occasion.

"Birthdays come every year," Hernandez shrugged. "One more doesn't make a difference."

EXTRA BASES:Dave Niehaus broadcast his 4,600th game with the Mariners on Wednesday, putting him 4,597 ahead of new partner Dave Sims in the booth. ... The Mariners' four top farm clubs open today, including debuts by the franchise's new teams in West Tennessee (Double-A) and High Desert, Calif. (Class A). The Triple-A Tacoma Rainiers open their season at Sacramento. ... In the misleading stat department, Julio Mateo's rocky relief effort Tuesday yielded a victory when Seattle came back to score four go-ahead runs in the bottom of the seventh. Mateo, who had given up two runs in the top of the seventh, has five consecutive wins over a stretch of 18 appearances. His 10 relief wins since the start of 2006 are tied for the major league lead with Matt Capps and Francisco Cordero. ... Any wonder about why Oakland struggled the first two games against Seattle could be answered by the A's 1-for-15 effort with runners in scoring position.